You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
Q: Would an application compiled as 64 bit by Harbour operate faster on a 64 bit machine vs the same application compiled as 32 bit on the same 64 bit machine?
Answer (by Przemek):
Yes it will. Mostly due to the cost of switching between kernel and
user space. In 64 bit mode we have extremely huge address space so
it's possible to set fixed addresses for user space and kernel space
and never reload memory descriptors when execution context is changed.
Here depending on the OS and type of application )how many times
system functions are called) the speed difference can be quite huge.
Additional speed up is also reached due to wider set of machine
instructions and completely new C ABI which uses extended 64-bit
registers to pass parameters when C functions are called. This
gives about 10-15% speed improvement in case of Harbour HVM.